近年来大城市交通拥堵严重，影响了人们的生活和经济发展，对此人们十分抱怨。假如你是李华，请根据以下要点用英语给报社写封信。
1.交通现状及影响；
2.提出改进建议；
3.希望建议被采纳。
注意：4.词数100左右；
5.可以适当增加细节，以使行文连贯；
6.开头语已为你写好，不计入总词数。
Dear editor,
I am writing to you to talk about the heavy traffic．
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Yours,
Li Hua
2021-2022学英语报答案试题答案
Mosquitoes have an extraordinary ability to target humans far away and fly straight to their unprotected skin. Regrettably, mosquitoes can do more than cause an itchy(发痒的）wound. Some mosquitoes spread several serious diseases，including Dengue，yellow fever and malaria.
Over one million people worldwide die from these diseases each year. New research now shows how mosquitoes choose who to bite.
Mosquitoes need blood to survive. They are attracted to human skin and breath. They smell the carbon dioxide gas, which all mammals breathe out. This gas is the main way for mosquitoes to know that a warm-blooded creature is nearby.
But mosquitoes also use their eyes and sense of touch. Michael Dickinson is a professor at the California Institute of Technology. His research shows how these small insects, with even smaller brains，use three senses to find a blood meal.
Michael Dickinson’s team used plumes—a material that rises into the air of carbon dioxide gas into a wind tunnel. They then used cameras to record the mosquitoes. The insects followed the plume.
Then, the scientists placed dark objects on the lighter colored floor and walls of the tunnel. Mr. Dickinson said, at first, the mosquitoes showed no interest in the objects at all. “What was quite striking and quite surprising is that the mosquitoes fly back and forth for hours. These are hungry females and they completely ignore the objects on the floor and wall of the tunnel. But the moment they get a hit of CO2, they change their behavior quite obviously and now would become attracted to these little visual blobs (斑点）.”
This suggested to the researchers that a mosquito’s sense of smell is more important in the search for food. Once mosquitoes catch a smell of a human or animal，they also follow visual signals.